package org.example.ch02.p23;

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int m=sc.nextInt();
        int s=sc.nextInt();
        int d=sc.nextInt();
        double totalSeconds=m*60+s;
        double hours=totalSeconds/3600;
        double miles=d/1.6;
        double speed=miles/hours;
        System.out.printf("%.2f",speed);
        sc.close();
    }
}
